Trifluralin, 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine, is a dinitroaniline (DNA) herbicide, and its herbicidal activity is described in The Pesticide Manual, Fifteenth Edition, 2009. Trifluralin, which acts as an inhibitor of microtubule assembly, provides pre-emergence control of many annual grass and broadleaf weeds in a variety of crops. Trifluralin has been in wide use since its introduction in the 1960s and certain weeds have developed a tolerance to both it and to other herbicides whose mode of action is that of acting as inhibitors of microtubule assembly. An effective replacement for trifluralin for the pre-emergence control of trifluralin-resistant weeds in crops would be useful.